Lots of good info on rust in this site. Have been reading about Phosphoric acid. Seems the consenses is to leave the gray residue on the metal before paintng. However, shouldn't the acid be nuetralized with Baking Soda or something prior to painting?

Thanks

Old Fool

08-30-2012 09:58 AM

This topic has as many opinions as there are people. Personally I would talk to the manufacturer of the primer I am going to apply over the bare metal and follow their directions.
What one manufacturer recommends may not be what a different manufacturer recommends.
At the cost of materials as well as my time I will not play home chemist and find out later on I didnt know what I was doing.
Call me lazy, but it is much easier to call BarryK and get the straight info before shooting his epoxy onto my project.

Richard1283

08-31-2012 02:33 AM

A sensible answer. I'm actually restoring a 1964 Triumph Bonneville motor cycle and am concerned about paint failure in all the seams, brackets and welds on the frame. Lots of hard to get at areas.

I'll contact the PPG rep and post his response.

Thanks

rusthater89

09-01-2012 07:02 PM

I've used naval jelly before on a metal sign. I applied epoxy and paint over it and it has held up for about a year now in humid hot summers and damp winters.

deadbodyman

09-02-2012 06:58 AM

I'm a big fan of Ospho but its a lot of work to remove rust with it.(even though you dont neutralize it) its even more work using it on a motorcycle frame. It does do two things that cant be disputed though,it REMOVES rust and protects bare metal from getting surface rust...many folks have had problems with primers having adheasion problems (bubbles and such) and there are reasons this happens that I wont get into right now. I suggest for first time users to use it for rust removal and the protection it provides but when it comes time to prime sand it off so there wont be any adheasion problems....
If it was me and I was doing a cycle frame I would do it the ez way and NOT use Ospho to remove the rust but use the electrolytic process.I'd buy a 10.00 kiddie pool deep enough to submerge the frame and 5.00 worth of "wash soda" NOT baking soda. all you do is drop the frame in the solution and connect a 12v battery charger or a battery and leave it for a day or two ,theres no easier or cheaper way to remove rust...

After THAT I would Ospho to protect the metal from surface rust if your not going to prime right away....but sand it off before priming,piece of cake.

Phoshphric acid products are like primers and paints ,theres many brands and they make a lot of promises they HAVE to be used properly. IMO, Ospho is THE best and the only one I use. That and epoxy primer is one hellava combination...I wont do a resto without it....or my SPI epoxy...

MARTINSR

09-02-2012 09:50 AM

If you are talking about a motorcycle frame, I don't think there is anything to even think about, you get the frame sand blasted and epoxy prime it! Bye bye rust!

Or, do as I did the last few motorcycles I had a hand in, bring all the "hard parts" to the powder coater and hand them to him, the next day pick them up with nice shiny black paint on them, dry, done, stick them in your trunk and bring them home to assemble. That is pretty darn hard to beat.

Brian

deadbodyman

09-03-2012 06:35 AM

Sure,except for a few things....Brian
Thats not a DIY
Powdercoaters are hard to find (around here anyway)
having the work done can get a bit expensive and you may have to wait a while to get it back.
Even if you sand blasted it yourself its messy and it wont be much fun, When I was doing electrolytic rust removal it was actually fun I through everything in sight that had rust in the tank,and I learned something...
Some guys just like doing everything themselves and thanks to sites like this they can talk to people of the same mind set...

Richard1283

09-04-2012 04:01 AM

Thanks for the responses. I'm a retired bodyman. In the old days I would sandblast everything and prime immediately. I didn't even Metal Prep because no mater how fast you dried it of after water wash you could see rust forming. But my little garage air compressor and suction feed blaster just will not do the job. I was hopeing to find a way to get around this but after much research I agree with MartinSR(sandblast is the only way to go). I'm going to have to get access to a pressure feed sandblaster and DIY, I don't trust anyone else to be as meticulous. Must be a reason that paint reps will not commit to putting their products over anything but "clean bare metal"

Here is a response from PPG. They also attached a PDF for the DX Treatments which I could post if any one is interested.

Dear Sir:

Thank you for your interest in PPG Refinish products. Based on the information you provided we would recommend our DX Metal Treatments. If after treating the metal with our DX579 and DX520 you still have rust, you will need new metal. You cannot prime over rusted areas, if you do blistering may occur.

We do not recommend crossing product lines therefore we do recommend you use one system such as Deltron throughout the entire process. Attached is the technical data sheet for the DX metal treatments.

If further assistance is required, please contact us at the Technical Service number listed below or visit us online at PPG Automotive Refinish.

We have established an automated faxing system that allows you to fax yourself product bulletins and MSDS 24 hours a day. The PPG FaxBack number is 800.647.6050 If you order document number 24747 from our FaxBack system, this document provides the instructions on how to use the system and the indexes that are available.

PPG Technical Service office is open Monday - Friday, 8:00-6:00 EST. This office can be reached at 440-572-6111 or FAX 440-572-6772. The
E-mail address is - reftechserv@PPG.com

Before using any PPG Refinish products, be sure you understand the warning messages on the labels of all components, since the mixture will have the hazards of all it's parts. Spray equipment must be handled with due care and in accordance with manufacturer's recommendations. Spraying of any material can be hazardous. PPG recommends the use of a fresh air supplied respirator with the use of any of our products. PPG REFINISH MATERIALS ARE DESIGNED FOR APPLICATION BY PROFESSIONALLY, TRAINED PERSONNEL USING PROPER EQUIPMENT UNDER CONTROLLED CONDITIONS, AND IS NOT INTENDED FOR SALE TO THE GENERAL PUBLIC.

Thank You,
Refinish Technical Service

deadbodyman

09-06-2012 08:59 AM

5 Attachment(s)

I used to be..Now I'm the Richmond county coroner...
Not really, but I work do with a lot of rusty cars and my last project was so rotted out everyone said it was dead and I should just bury it..Little by little as the work progressed they all stopped laughing and started giving me nicknames ,"The Deadbodyman" stuck or DBM ,my son came up with it.personally I prefer BDBM the B stands for brain....Anyone that will take on something like this has some serious "metal" illness issues...(and I'd like to meet them)
Heres a few old pics to get an idea of what can be done without ANY media blasting,basiclly just a heavy wire cup on a side grinder and Ospho to remove rust,then epoxy primer,after 10 years (most outside) no rust poping through or blisters. any time a company says only use thier products as a system its TOTAL BULLS*IT.....But then again I like using the best product available for the application so I dont use ANY PPG products with the exception of "Omini Plus" base coat when I need something cheap,its actually some of the best cheap base out there. I would have you notice PPG or any of the paint companies wonT say DONT use any other products with thiers its always "We dont recomend" using any other products with ours.In the 35 yrs of doing this work I've never used any one brand from start to finish. theres a few brands that in my opinion are simply the best out there and I wont (not cant) substitute,like Ospho for rust,SPI epoxy primer, and SPI clear.

cyclopsblown34

09-06-2012 09:32 AM

BDBM, that car is too cool. The PC term for that is Bovine Scatology, not the bodyman's way of being emphatic and saying them potty mouth words.:D

Lizer

09-06-2012 10:54 PM

I disagree; bovine scatology is misleading and flawed.

Scatology in itself would mean the study of scat, but nothing is being studied, it's being proclaimed.

Secondly, referring to the species alone with no reference to the sex is ambiguous. There is obviously some significance to having the excrement originate from a bull otherwise the phrase never would have been coined the way it is.

So while you can use any colorful synonym for sh1t all you want, it should be preceded by 'male bovid.' Or just bull.

That is male bovid scat.

cyclopsblown34

09-07-2012 09:58 AM

Quote:

Originally Posted by Lizer
(Post 1588924)

I disagree; bovine scatology is misleading and flawed.

Scatology in itself would mean the study of scat, but nothing is being studied, it's being proclaimed.

Secondly, referring to the species alone with no reference to the sex is ambiguous. There is obviously some significance to having the excrement originate from a bull otherwise the phrase never would have been coined the way it is.

So while you can use any colorful synonym for sh1t all you want, it should be preceded by 'male bovid.' Or just bull.

That is male bovid scat.

I almost can't type I'm laughing so hard. Thanks for the dissemination of my flawed statement. Honest, i really appreciate this and the laugh I'm getting. you're obviously better edumicated than I iz. You DA MAN!!!!!

Lizer

09-07-2012 10:46 AM

Quote:

Originally Posted by cyclopsblown34
(Post 1588985)

I almost can't type I'm laughing so hard. Thanks for the dissemination of my flawed statement. Honest, i really appreciate this and the laugh I'm getting. you're obviously better edumicated than I iz. You DA MAN!!!!!

how sad is it that one of the few posts in which I'm thanked is one on my thoughts of male bovid scat. Well would you believe it I'm a scientist by profession (veterinary microbiologist by academic qualification) so while my contribution is rather small around here it's nice when I can be of use :thumbup: